Cloth cutting machine



Nov. 10, 1936. M- GREENBAUM 2,060,197

CLOTH CUTTING MACHINE Filed April 2l, 1936 Sheets-Sheet l IIIIII llllllllllllll"""" f3] BY jf @d ram ATTORNEY.

Nov. 10, 1936. MGREENBAUM CLOTH CUTTING MACHINE Filed April 21, 1936 4 Sheets-Sheet 2 3/ sa 30 za Z5 ,e7 T z3 7 l 34 j E ,Z0 L g -Ja l J/j/ 5i: 33 .PH

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I H X// I n l t 3- m' fw ff ik INVENT OR.

ATTORNEY.

N0'v.1o,1936. y M GREENBAUM i 2,060,197

CLOTH CUTT ING MACHINE Filed April 2l, 1956 4 Sheets-Sheet 5 f ATTORNEY.

Nov., 10, 1936.

M. GREENBAUM 2,060,197

CLOTH CUTTING MACHINE Filed April 21, 193e 4 sheets-sheet 4 ATTORNEY.

APatented Nov. 10, 1936 UNITED sTATEs PATENT oEFicE CLOTH CU'rTmG MACHINE Martin Greenbaum, Newark, N. J.

Application April 21, 193s, serial No. '15,522

19c1aims. (c1. 164-75) "This invention relates, generally, to cloth cutting machines, and the invention has reference, more particularly, to a novel improved cloth cutting machine of the straight knife or reciprocating type having means for sharpening the knife thereof.

Heretofore, various attempts have been made to produce cloth cutting machines having sharpening mechanisms for keeping the knives thereof in sharp condition, the said mechanisms generally employing grinding wheels that are either hand or power-driven and are adapted to grind opposite sides of the cutting edge of the knives. Such sharpening mechanisms, however, have not been commercially practicable for various reasons among which may be mentioned that owing to the short, rapid reciprocating .motion of the knife, the grinding wheels cannot be driven so as to successfully sharpen the knife by frictional contact and-furthermore great difficulty is experienced in providing mechanism for moving the wheels or stones along the 'edge of the knife while rotating the same and applying the same with proper pressure to thefsides of the knife blade. In my copending application Serial No. 28,799 I have disclosed a novel practical sharpening mechanism for cloth cutting machines, the said mechanism employing power driven belts having abrasive material ontheir surfaces for engagingand sharpening the knife edges.

The principal object of the present invention is to provide additional and improved sharpening mechanisms for cloth cutting machines, the l said mechanisms employing, however, the fundamental idea of abrasive belts disclosed in my copending application. f g

Another object o f the present invention lies in the provision of sharpening mechanisms for cloth cutting mechanisms of the above character having improved means for driving andgreciprocating the belts together with improved means for applying -the belts to the knife edges for sharpening the latter.

Other objects of this invention. not at this time more particularly enumerated, will be clearly understood from the following detailed description of the same.

The invention is clearly illustrated in companying drawings, in which:

Fig. 1 is a perspective view illustrating the novel cloth cutting machine in use.

Fig. 2 is Lan enlarged view in front elevation with parts broken away of a portion of the structure of Fig. 1, the sharpening mechanism being in inoperative position.

the ac- Fig. 2A is a fragmentary sectional view taken along line 2A-2A of Fig. 2. o

Fig. 3 is a View similar to Fig. 2 but shows the sharpening mechanism in operation.

Fig. 4 is a side view of the machine with parts broken away.

Fig. 5 is an enlarged sectional view taken along line 5-5 of Fig. 4.

Fig. 6 is a view in front elevation with parts broken away of a somewhat modified structure.

Fig. 7 is a side view of the structure of Fig. 6 with parts broken away.

Fig. 8 is a view in front elevation of another modified form of the invention.

Fig. 9 is an enlarged sectional view taken 4along line 9-9 of Fig. 8.

Fig. 10 is a sectional view taken along line Ill-I0 of Fig. 9. i

Fig. 11 is a sectional view taken substantially along line II-II of Fig. 4, but--with the sharpening mechanism in its lower operating position, and I Fig. 12 is an enlarged fragmentary view in ele;

,vation `taken along the line I2-I2 ink Fig. 8

looking in the direction of the arrow.

over a supporting surface, such as a table top 3,

and beneath a lay of cloth or other fabric 4, when cutting such fabric. A standard 5 extends upwardlL from base 2 and has the machine casing 5 supported upon the top thereof. Casing 6 car` ries a motor 'I which is adapted to reciprocate the cutting knife or blade 8 by means of a crank pin 9 and connecting rod I0 enclosed within the casing 5. The knife 8 reciprocates within a slide bearing I I provided in the standard 5. A vertically adjustable guard or rod I2 is positioned in advance of the blade 8 for protecting the fingers of the user. The guard I2 extends upwardly through a bracket I3 carried by the forward portion of casing 6 and is provided with a rack I4 at its other end. By pressing upon the lever I8 (see also Fig. '1) the stop pin I5 may be moved out of engagement with the rack I4, thereby permitting the manual raising or lowering of the guard I2. The guard I2 carries a presser foot or member I9 that is adapted to rest upon the goods being cut.' thereby serving to hold the goods down and preventing their vibrating due to reciprocation of blade 8. The apparatus thus far described is old and well known to those skilled in the art and would appear to require no further description. v

According to the preferred construction, the crank disk 20 driven by the motor 1 and having the crank pin 9 thereon, has its peripheral surface knurled at 2l and is shown as of V-shape in cross section for engaging and driving a friction wheel 22 that is rotatably mounted upon a stud 23 and serves to drive a bevel gear 24. 23 and gear 24 are carried by a vertically movable frame 25 that is slidable on guides 26 (see Fig. 2) provided on the machine casing 6. Coil springs 21, acting. between the upper part of machine casing 6 and the frame 25, urge this frame downwardly tending to cause friction wheel 22 to move downwardly and into engagement with the crank disk 20.

A headed pin 28 is vertically slidable within a guide aperture provided in the frame 25 and cooperates with arpivoted latch member 30. Latch member 30 is pivoted on a screw 3I to swing in a horizontal plane, the said latch being adapted to overlie the headed pin 28, as show n in Figs. 1, 2 and 4, or to moving outwardly out of contact with the headed end of this pin, as shown in Fig.

Stud I 3. -A stop screw 32 is adapted to engage the latch 30 when the same is in overlying -abutting relation to the pin 28, as shown in Fig. 4.

When the sharpening mechanism is not in use,

-the latch 30 is positioned so as to abut the top of pin 2 8 in which position of these members, a vertical shaft 33, aligned with pin 28, abuts the lower end of this pin and by a/cting through this pin and latch 30 serves to hold the frame 25 in Vits upper position, as shown in Figs. 2 and 4, in

which position the friction wheel 22 is out of engagement with the crank disk 20. `By turning latch 30 to one side, as shown in Fig. 3, the pin 28 permits the frame 25 to slide downwardly thereover and over a tubular shaft 34 surrounding the shaft 33 until friction wheel 22 engages crank disk 20. 'Ihe said shaft 34 cooperates with the guides 28 in guiding the frame 25 inits vertical movement. Shaft 34 extends through l guide bearings provided on the forward part of casing and has its lower portion splined as by a key 35 and spline 36 to the vertical shaft 33.

Bevel gear 24 meshes with another bevel gear 31 that is splined upon the tubular shaft 34 so that as gear 31 rotates under the drivingaction of gear 24 the tubular shaft 34 will rotate and drive the interior shaft 33. Interior shaft 33 has a gear 38 (see Figs. 2 and 5) secured to its lower portion, which gear meshes with two other gears 33 and 40. Gear 39, see especially Figs. 2 and 2A is fixed upon a vertical shaft 4I within a gear housing 42. Shaft 4I extends upwardly into a slide bearing 43 provided in the forward portion of casing 6 and is provided with spiral drive grooves 44 that cooperate with a pin 45 carried by the bracket I3. Thus, it will be apparent that the turning of shaft 33 will cause gear 38 to drive gear 39, thereby rotating shaft 4I and causing pin 45, projecting into spiral grOQvS u. t@ effect vertical reciprocation of shaft 4I and of the gear casing 42 carried thereby.

Y The lower end portion of shaft 33 carries a pulley 41 that serves to drive a belt 48 which belt extends rearwardly and around an idle pulley 49 carried by a bracket 50 provided on the gear housing 42. The idle pulley 49 is shown as provided with a tensioning spring 5I that serves to retain belt 48 in tight condition. The gear 40 is iixed upon a vertical stub shaft 52 journaled inthe gear housing 42 and having a pulley 53 fixed upon its lower end portion. Pulley 53 carries 'a belt 54 that extends rearwardly and around an idle pulley 49' that is carried by a bracket 50 in a manner similar to that in which idle pulley 49 is carried. The lts 48 and 54 are similar to the belts shown in my copending application, and have their exterior surfaces covered with abrasive material for effecting the sharpening of the knife 8. These exterior surfaces of the belts, i. e. the surfaces that contact with the knife 8 have their upper and lower edges inwardly turned or beveled to prevent the knife 8 from cutting these belts.

Idler pulleys 49 and 49' are spaced further `apart than the driving pulleys 41 and 53 so that the inner runs of these belts diverge away from each other and would not of themselves engage the edges of knife 8 for sharpening the same. Engagement of the inner -runs of the belts 48 and 54 with the knife edges is accomplished by means of pivoted shoe members 55 and 55 (see y Fig. 11). These shoe members are respectively pivoted on pivot pins 56 and 56' carried by the brackets 50 and 50 respectively, and have fiattened cuter or forward end portions for engaging the inner surfaces of the runs of the belts for pressing these inner runs outwardly and into engagement with opposite side edges with the knife or blade 8. Coiled torsion springs 51 and 51 have one of their ends respectively engageable in any one of a. plurality of apertures 58 provided in the brackets 50 and 50' and the other ends engaging the respective shoe members 55 and 55' for resiliently pressing these shoe members against the inner runs of the belts. thereby serving to resiliently press these runs of the belts against the side edges of the knife 8 for sharpening the same. By adjusting the springs 51 and 51 with respect to the apertures 58 the shoe members may be pressed with any desired pressure against the belts, thereby causing these belts to engage the side edges of the knife 8 with desired sharpening pressure.

When the sharpening mechanism is in its upper inoperative position, as shown in Figs. 1, 2, 4 and 5 the inner runs of the belts 48 and 54 abut camming projections 60 and 60 provided on the upper side surfaces of the standard 5, whereby these belts are held out of rubbing engagement with the knife 8 during the normal operation of the machine so that undue wea'r of the belts is prevented.

In operation, assuming that the motor 1 is running and that it is desired to sharpen the knife 8 the operator merely turns the latch 30 from abutting relation with respect to headed pin 28, shown in Figs. l, 2 and 4, to the out of the way position shown in Fig. 3, whereupon the springs 21 immediately serve to press the frame 25 downwardly with gear 31 sliding over tubular shaft 34 until friction wheel 22 engages the crank disk 20. Crank disk 20 immediately starts to drive wheel 22 which acts through gears 24 and 31, tubular shaft 34, solid shaft 33, and gears 38 and 39 to cutting edge of knife 8. At the same time. the

driving pulleys 41 and 53 serve to drive these belts so that their abrasive surfaces rub over the sides of the knife edge thereby sharpening the same, the belts being applied with the desired resilient and yielding pressure against the sides of the knife edge by the action of the spring pressed shoe members 55 and 55.

The shoe members 55 and 55 not only serve to apply the belts 48 and 54 with just the right pressure to the knife edge, but they also apply these belts at just the right angle of approach to secure the most rapid and efficient sharpening of the knife edge. In the sharpening of the knife 8 the belt 48, being lower than the belt 54 actually presses downwardly beyond the lower end of knife 8, and in order to prevent the shoe member 55 from thrusting the belt 48 outwardly into the path of movement of the lower sharpened end of this knife, this shoe member 55 is provided with a flat vertical stop portion |08, as shown especially in Fig. 10, which stop portion by slidingly abutting th'e side of the knife 8 when belt 48 moves below this knife, prevents the belt from getting into the path of movement of the knife and hence prevents injury to the belt and possible damage to the knife Vor shoe member 55. When the knife edge is sharp, which only takes a few moments, the latch 30 is moved into overlying relation to -the headed pin 28 at a time when this pin is in its low position which occurs each time the sharpening mechanism moves downwardly. Upon the next upward movement of the sharpening mechanism, the solid shaft 33 in moving upwardly within hollow shaft 34 abuts the lower end of headed pin 28 and continued upward movement of the shaft 33 serves to press pin 28 upwardly, whereby the latterv by pressing upon latch 30 serves to raise frame 25 upwardly to its original position with the friction wheel 22 out 'of engagement with crank disk 20, in which position the parts of the sharpening mechanism come to rest. In this inoperative position of the sharpening mechanism, the camming projections 68 and 60 ser've to hold the belts out of engagement with the knife edge, the mechanism being now ready for another sharpening operation when desired.

The shape of the end portions of the shoe members 55 and 55 is made such as to give the knife edge the desired bevels at the sides thereof,

the angles of the bevels being determined by the angle of inclination of the end portion of the shoe member. In those knives having `one straight side and the other side beveled the shoe members are appropriately shaped for maintaining such shape of the knife.

In the form oi the invention shown in Figs. 6 and 1 a somewhat different type of drive is employed for operating the sharpening mechanism and in this form of the invention the belts are reciprocated vertically by hand. Referring now to these figuresthe shaft 8| vof motor 1' is provided at its rear with a clutch member 52 that is adapted' to cooperate with another clutch member 53 having a pinion 64 fixed thereon. A coil compression spring 65 tends to urge clutch member 53 into engagement4 with clutch member 52 and a wedge 65 normally serves to hold the clutch members 62 and 63 out of engagement against the tension of spring 65. Pinion 64 ydrives an idler gear 61 which in turn drives a gear 68 fixed on shaft 69. extends forwardly and has a spiral gear 10 there? on for driving asecond spiral gear 1| flxed on a tubular shaft 34. Shaft 34 extends vertically within suitable bearings provided with-- in the forward portion of the machine casing 6 and is-splined, as by a key 13 and a spline 14, to an inner shaft 33' similar to shaft 33 of the form of invention shown in Figs. 1 to 5. The lower portion of shaft 33' extends into a gear housing 42 and has a gear 38 fixed thereon that meshes with a gear 40' fixed on a stub shaft 52'.

Lower end portion of shaft 33 carries a pulley Shaft 69- 41 as in the form of the invention shown in all as in the manner described and shown in the previous form of the invention. Pivoted shoe members 55 and 55' are also employed in this form of the invention for holding the belts against the knife 8 to effect the sharpening of the same. The camming projections 60 and 60' are also employed in this form of the invention.

The sharpening mechanism in this `forrn of the invention is normally held in raised position by a. pivoted latch 15 that is pivoted at 15 upon the machine casing 6 and has a lower hooked portion for engaging beneath a projection 11 provided on the gear housing 42'. A headed plunger 18 is mounted on the forward part of casing 6' and has a shank portion 19 for engaging a clutch lever 80 that is pivoted at 8| upon the casing 6'. Clutch lever 80 has its rear end portion engaged in an aperture provided in a link 82 connected to the wedge 66. The shank 19 of plunger 18 is also adapted to engage the latch 15. A coll spring 83 surrounding., the stem of plunger 18 serves normally to hold thisplunger forwardly so that its shank 19 does not engage clutch lever 88 or link 15. A handle 84 is provided on the forward portion of gear housing 42 for use in reciprocating the sharpening mechanism manually.

In use, when it is desired to sharpen the knife b ade 8 the lever I8 is pressed towards casing 6 so as to release rack or guard I2 whereupon this rack may be moved downwardly to its lowermost position, shown in Figs. 6 and 1. The plunger'18 is then pushed inwardly, thereby moving vlatch 15 out of engagement with the projection 'E1 and at the same time actuating clutch lever 8f! counterclockwise as viewed in Fig. '1, thereby effecting the raising of link 82 and the raising of wedge 66 to permit spring 65 to expand and engage clutch member 63 with clutch member 62. The motor 1' now serves to rotate gears 64. 51, 58. 18 and 1|, thereby causing the tubular shaft 34 to drive the solid shaft 33' and effect the driving of the belts or strips 48 and 54. By grasping the handle 84-the sharpening mechanism is reciprocated vertically by hand thereby effecting the sharpening of the knife 8. When the sharpening operation is complete, the handle 84 is moved all the way up until latch 15 again engages under projection 11, thereby supporting the sharpening mechanism in its upper out ofthe way position. Just before latch ible shaft 88.

15 engages under projection 11, the top of this projection abuts the lower end of clutch lever 80 and swings this clutch lever clockwise (see Fig. 7) .thereby depressing link 82 and wedge 66 causing disengagement of clutch 62-93 and disconnecting the drive of the sharpening mechanism. By pressing upon lever` I8 the guard I2 may be again raised preparatory to using the machine for cutting goods.

In the form of the invention shown in Figs. 8, 9, 10, and 12 the drive for the sharpening mechanism is similar to that shown in Figs. 1 to 5 and similar parts are similarly numbered. In these figures the solid shaft 33 has a bevelled gear 86 xed upon its lower portion which gear meshes with a bevel gear 81 that drives a iiex- Shaft'88 drives a pinion 89 that meshes with a similar pinion 90, both of which pinions are adapted toselectively engage the teeth I4' of rack I2. Pinions 89 and 98 are carried by a shiftable member 9| that is oscillatably mounted upon a pin 92 carried by a bracket 93. The shiftable member 9| has projections 94 and 94' thereon for engaging stops 95 and 98 respectively. Stop 95 is carried by the lower end by a vertical rod 91 that is attached at its upper end to the vertically movable frame 25, whereas stop 96 is carried by the lower portion of rack or guard I2.

A coil compression spring 98 is carried by the shiftable member 9| and bears at one Yend against this shiftable member and at its other end against a projecting lug 99 formed on the bracket 93 for holding either pinion 89 or pinion 99 in mesh with rack I4'. When pinion 89 engages the rack I4 the drive is such as to elevate or raise the sharpening mechanism and when pinion 99 engages the rack I4' the drive is such as to lower the sharpening mechanism. Thus, in use when the latch member 38 is turned so as to permit downward movement of frame 25, thereby completing the drive for shaft 33 in the manner eX- plained in connection with Figs. 1 to 5, the shaft 33 will revolve, thereby driving the abrasive belts or strips 48 and 54. At the same time, the rod 91 in moving downwardly with frame 25 causes stop 95 to engage projection 94l and actuate the shiftable member 9| about the pin 92 so that pinion engages the teeth of rack I4. The operation of shaft 33 also causes gear SG to drive gear 81 which in turn drives flexible shaft 88 and gears 89 and 90 to effect downward movement of the sharpening mechanism, thereby serving to sharpen the knife 8. When the vsharpening mechanism has reached the lower end of its travel, the projection 94' engages the stop 96 at the bottom of rack I4', which stop serves to swing the shiftable member 9| back into its full line position shown in Fig. 8, in which position pinion 99 engages the teeth of rack I4' so that the sharpening mechanism thereafter moves upwardly. Thus, the sharpening mechanism continues to move upwardly and downwardly to eifect the sharpening of the knife, the upper and lower limits of its travelbeing determined by stops and 96. After the knife has been sharpened the latch member 38 is swung into abutting relation with respect to the headed pin 28, thereby stopping the sharpening mechanism at the upper end of its travel in much the same manner as described in connection with Figs. 1 to 5. By now releasing the spring pressed stop pin I5, the guard l2 may be raised. lthe shiftable members 9| turning somewhat permit the temporary disengagement of pinion 89 with the rack, whereupon the machine is ready for its cutting operation.

It will be noted that either of the belts 48 and 54 may be readily slid downwardly and off of its supporting pulleys and replaced by a new belt when the same becomes worn in use.

As many changes could be made in the above construction and many apparently widely different embodiments of this invention could be made without departing from the scope thereof, as defined by the following claims, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

I claim:

1. In a cloth cutting machine having a driving motor, a reciprocable knife driven from said motor, and means for sharpening said knife, said means comprising belts arranged to be driven from said motor for engaging opposite sides of the cutting edge portion of said knife, and yieldable shoe members for pressing said belts with desired pressure against said sides of the knife cutting edge portion.

2. In a cloth cutting machine having a driving motor, a reciprocable knife driven from said motor, and means for sharpening said knife, said means comprising belts arranged to be driven from said motor, said belts having abrasive material adhered thereto, and spring pressed shoe members for pressing said belts against opposite sides of the cutting edge portions of said knife to effect the sharpening thereof.

3. In a cloth cutting machine, the combination with Van endwise reciprocating knife having a longitudinal cutting edge, of means for sharpening the knife edge comprising a exible sharpening strip having an abrasive surface yieldingly contacting with the knife edge, and mechanism for propelling said exible strip to sharpen the knife edge comprising a motor-driven wheel. a second wheel movable into and out of driving relation with said i'lrst wheel and drive connection from said second wheel to said flexible strip.

4. In a cloth cutting machine, the combination with an endwise reciprocating knife having a longitudinal cutting edge, of means for sharpening the knife edge comprising a iiexible sharpening belt having an abrasive surface yieldingly contacting with the knife edge, and mechanism for propelling said iiexible belt to sharpen the knife edge comprising a motor-driven wheel, a second wheel movable into and out of driving relation with said first wheel, and mechanism driven by said second wheel for propelling said flexible belt lengthwise and also for moving said exible strip along the knife edge.

5. In a cloth cutting machine, the combination with an endwise reciprocable knife having a longitudinal cutting edge, and a motor for reciprocating said knife, of means for sharpening said knife edge comprising a flexible sharpening strip having an abrasive surface yieldingly contacting the knife edge, and drive mechanism for propelling said flexible strip to sharpen the knife edge comprising a wheel driven by said motor, a second wheel movable into and out of driving relation with said rst wheel, and drive connections from said second wheel to said flexible strip.

6. In a cloth cutting machine, the combination with an endwise reciprocable knife having a longitudinal cutting edge, and a motor for reciprocating said knife, of means for sharpening said knife edge comprising a flexible sharpening strip having an abrasive surface yieldingly contacting the knife edge, and drive mechanism for propelling said exible strip to sharpen the knife edge comprising a wheel driven by said motor, a second wheel movable into and out of driving relation with said first wheel, and mechanism driven by said second wheel for propelling said flexible sharpening strip lengthwise and also for moving the flexible strip along the knife edge.

7. In a cloth cutting machine, the combination of an endwise reciprocating knife having a longitudinal cutting edge, of means for sharpening the knife edge comprising a flexible sharpening belt having an abrasive surface yieldingly contacting the knife edge, a motor, a telescopic shaft driven by said motor, and mechanism driven by said telescopic shaft for propelling said flexible belt to sharpen the knife edge and also for moving the' flexible belt lengthwise along said knife edge. l

8. In a cloth cutting machine, the combination with an endwise reciprocable knife having a longitudinal cutting edge, and a motor for recipro-- cating said knife, of means for sharpening the knife edge comprising a flexible strip having an abrasive surface yieldingly contacting the knife edge, and drive mechanism for propelling -said flexible strip to sharpen the knife edge, comprising a telescopic shaft driven by said motor, and drive connections between said telescopic shaft and said flexible strip.

9. In a cloth cutting machine, the combination with an endwise reciprocable knife having a longitudinal cutting edge, and a motor for reciprocating said knife, of sharpening elements for said knife edge, a telescopic shaft arranged parallel with said knife and driven by said motor, and mechanism operated by said telescopic shaft for propelling said sharpening elements to sharpen the knife edge and also for moving said sharpening elements lengthwise along said knife edge.

10. In a cloth cutting machine having an upright endwise reciprocating knife at the front p'ortion of the machine and having an uprightcutting edge, sharpening means for said knife edge comprising converging flexible abrasive belts, means for pressing said belts yieldingly against opposite sides of the knife edge, and drive mechanism for propelling said abrasive belts lengthwise comprising a motor, an upright shaft adjacent the knife, drive connections at the front portion of the machine between said motor and shaft, and drive connections between said shaft and said abrasive belts.

11. In a cloth cutting machine having an upright endwise reciprocable knife at the front portion of the machine and having an upright cutting edge, a motor for reciprocating said knife, sharpening means for said knife edge comprising converging flexible abrasive strips yieldingly contacting opposite sides of the knife edge, and drive mechanism for propelling said abrasive strips lengthwise comprising an upright shaft adjacent the knife, drive connections at the front portion of the machine between said motor and said shaft, and drive connections between said shaft and said abrasive strips'.

12. In a cutting machine having an upright endwise reciprocable knife at the front portion of the machine and having an upright cutting edge, a motor for reciprocating said knife, sharpening means for said knife edge comprising converging flexible abrasive strips yieldingly contacting opposite sides of the knife edge, and drive mechanism for propelling said abrasive strips lengthwise comprising an upright telescopic operated by said telescopic shaft for moving said abrasive strips lengthwise along the knife edge.v

13. In a cutting machine having an upright endwise reciprocable knife at the front portion of the machine and having an upright cutting edge, a motor for reciprocating said knife, sharpening means for said knife edge, drive mechanism for said sharpening means located at the front portion of the machine and comprising an upright shaft, drive connections from the motor to said shaft and from the shaft to said sharpening means, and means including a-rotary and endwise movable helically grooved shaft for moving said slarpening means lengthwise along the knife e ge.

14. In a cutting machine having an upright endwise reciprocable knife at the front portion of the machine and having an upright cutting .edge,'a motor for` reciprocating said knife, sharpening means for said knife edge, drive mechanism for said sharpening means located at the front portion of the machine and comprising an uprightshaft, drive connections from the motor to said shaft and from the shaft to said sharpening means, and a rack and pinion vreciprocating mechanism operated by said upright shaft for moving said sharpening means lengthwise along the knife edge.

15. In a cutting machine havingan upright endwise 'reciprocable knife at the front portion of the machine and having an upright cutting edge, a motor for reciprocating said knife, sharpening means for said knife edge, said sharpening means comprising a pair of exible belts and means for applying said belts against the sides of said knife edge, drive mechanism for said sharpening means located at the front portion of the machine and comprising an upright shaft, drive connections from the motor to said shaft and from the shaft to said sharpening means,

and a rack and pinion reciprocating mechanism operated by said upright shaft for moving said slarpening means lengthwise along the knife e ge.

16. In a cutting machine having an upright endwise reciprocating knife at the front portion of the machine and having an upright cutting edge, sharpening means for said knife edge comprising converging flexible abrasive strips, means for causing said strips to yieldingly contact opposite sides of the knife edge, drive mechanism for propelling said abrasive strips lengthwise, and means forremoving said strips from said knife edge when said sharpening means is not in use.

17. In a cutting machine having an upright endwise reciprocating knife at the front portion of the machine and having an upright cutting edge, sharpening means for said knife edge comprising converging, horizontally disposed, flexible abrasive strips yieldingly contacting opposite sides of the knife edge, drive mechanism for propelling said abrasive strips lengthwise, means for simultaneously raising and lowering said 'strips to effect the sharpening of said cutting edge, and cam means for disengaging said abrasive strips from said 'cutting edge at the end of the sharpening operation.

18. In a cloth cutting machine having a driving motor, a reciprocable knife driven from said xnotor, and means for sharpening said knife, said means comprising belts arranged to be driven from said motor for engaging opposite sides of the cutting edge portion of said knife, and yieldable shoe members for pressing said belts with -desired pressure against the sides of the knife cutting edge portion, at least one of said shoe members having stop means for engaging the side of the knife when the belt pressed thereby moves below the lower end of the knife, thereby keeping the belt outof the path of movement of the knife.

19. In a cloth cutting machine having a driving motor, a. reciprocable knife driven from said motor, and means for sharpening said knife, said means comprising vertically staggered belts arranged to be driven from said motor for engaging opposite sides of the cutting edge portion of said knife, means for vertically reciprocating said belts to eiect the sharpening of the knife all along its cutting edge, and yieldable shoe members for pressing said belts with desired pressure against the sides ofthe knife cutting edge portion, the shoe member engaging the lower of said belts having stop means for engaging the side of the knife when the belt pressed thereby moves below the lower end of the knife, thereby keeping the beltl out of the path of movement of the knife.

MARTIN GREENBAUM. 

